Search

A self-assembled three-dimensional (3-D) MoS2 microsphere-based memristor with a favorable ON/OFF resistance ratio of ~104, endurance, and retention time is demonstrated at room temperature. The formation and rupture of a localized Ag metallic filament, establishment and destruction of a boundary-based hopping path, and charge trapping and detrapping from the space charge region co-contribute to the bipolar resistive switching memory behaviours observed in the device of Ag/MoS2/ITO. This work may give insight into the mechanism of the resistive switching memory behaviours of a device with a 3-D micro-scale. [ABSTRACT FROM AUTHOR]

The elastic and structural properties of nanolaminate Zr2InC are studied by first-principles, and it is shown that, for any used modes, including the generalized gradient approximation (GGA) and localized density approximation, there always exists an ultraincompressibility along c axis between 70 GPa and 400 GPa. Such anomalous behavior is originated from the slowdown of core-valence charge transfer. The rapid shift of Zr atom along c axis also contributed much to the ultraincompressibility as it is greatly reduced once the Zr atom shift suspends along c axis above about 400 GPa. Both the elastic constants and the phononic vibrational frequencies investigations confirmed the structural unstable simultaneously. The Poisson's ratio investigations observed a higher ionic or weaker covalent contribution in interatomic bonding and the degree of ionicity increases with pressure. [ABSTRACT FROM AUTHOR]

The thermal behavior of aluminum nanoparticles reacting with propylene oxide was investigated in normal incident shock waves. Their reactive temperature, which is about 2705±150 K, was experimentally determined by the emission strength of AlO. The reactive products were evaluated by x-ray diffraction, which shows that several different phases of Al2O3 are produced in different temperature regions. The scanning electron microscopy image of the reactive products shows that some holes, which were produced in the process of aluminum nanoparticles violently reacting with suboxides of aluminum, are found on the surface of the products. The data of transmission electron microscopy indicate that the grain diameters of the products were within the range of 20–90 nm. The geometry of propylene oxide was calculated and optimized using the Rb31yp function and the 6–311+g(d,p) basis set. The calculated results show that the diameter of the molecule is about 0.435 nm. The process of vaporizing and condensing of propylene oxide was investigated by electron microscopy, and the results show that the average drop diameter is 4.03 μm at t=70 s and then is 2.06 μm at t=120 s. It suggests that the average drop diameters tend to range from several nanometers to tens of nanometers, which is very close to the diameter of aluminum nanoparticles (average of 70 nm). Thus, we may consider them to react with each other in the gas phase in normal incident shock waves in the experiment. [ABSTRACT FROM AUTHOR]

The recombination property of nitrogen (N)-related acceptor-bound states in ZnO has been investigated by photoluminescence (PL), time-resolved PL, and selective PL. Several possible recombination processes were discussed by analyzing the relaxation and recombination properties under large Coulomb interaction. It is strongly suggested that bound exciton emission dominates the recombination process related to the N acceptor. The recombination lifetime is 750 ps and the binding energy is 67 meV for N-acceptor-bound exciton at low temperature. [ABSTRACT FROM AUTHOR]